Three rack dishwasher

ABSTRACT

Abstract of the Disclosure 
         
   An improved dishwasher is provided with a lower rack, a middle rack, and an upper rack.  Each rack has a spray arm associated therewith.  A fourth spray arm may also be provided for enhanced cleaning of objects in the racks.  The lower rack is a low profile tineless rack for holding flat and shallow objects.  The middle and upper racks have bottom portions sloping in opposite directions so as to accommodate larger items, such as dinner plates, in each rack.  The middle and upper racks are independently vertically adjustable with respect to one another.

Detailed Description of the Invention Background of Invention

[0001] Dishwashers typically have an upper and lower rack for holdingobjects to be washed. The racks of different manufacturers have numerousconfigurations to provide various loading arrangements for the objects,such as plates, bowls, glasses, silverware, pots and pans. Theseconventional two rack dishwashers normally have upper and lower sprayarms to deliver water to wash and rinse the objects in the racks.

[0002] Dishwashers have also been designed with three racks, such as inU. S. Patent No. 3,837,917, and 3,861,769. However, such three rackdishwashers do not have separate spray arms for each rack, but ratherrely upon a telescoping spray tower to supply wash and rinse water toone or more of the racks. Such spray towers are less effective incleaning than rotating spray arms which have a better spray pattern thana spray tower.

[0003] Accordingly, a primary objective of the present invention is theprovision of a dishwasher having three racks with separate spray armsfor each rack.

[0004] Another objective of the present invention is the provision of adishwasher having three racks, wherein the upper two racks have bottomportions which slope or step in opposite directions so as to maximizeloading options and usefulness of the racks.

[0005] A further objective of the present invention is the provision ofa dishwasher having a flat lower rack without or substantially withouttines, and middle and upper racks with tines.

[0006] Still another objective of the present invention is the provisionof a dishwasher having three racks, with at least the upper two racksbeing vertically adjustable independent of one another.

[0007] These and other objectives will become apparent from thefollowing description of the invention.

Summary of Invention

[0008] A dishwasher is provided with three racks mounted in the washingchamber for movement between an extended loading position substantiallyoutside of the washing chamber, and a retracted washing position withinthe washing chamber. Three spray arms are provided in the dishwasher sothat there is one spray arm associated with each of the racks. A fourthspray arm may also be provided for enhanced cleaning of the objects inthe racks. The middle and upper racks have bottom portions sloped orstepped in opposite directions so as to allow tall objects, such asdinner plates, to be placed in both racks. The bottom rack is flat andwithout or substantially without tines so as to receive low profileobjects, such as cake pans, cookie sheets and frying pans. The middleand upper racks are independently vertically adjustable.

Brief Description of Drawings

[0009]Figure 1 is a front elevation view showing a dishwasher having thethree racks of the present invention.

[0010]Figure 2 is a perspective view from the right front corner showingthe three racks and the associated spray arms.

[0011]Figure 3 is a view similar to figure 2 from the left front corner.

[0012]Figure 4 is a front elevation view of the racks and spray arms.

[0013]Figure 5 is a left side elevation view of the racks and sprayarms.

[0014]Figure 6 is a right side elevation view of the racks and sprayarms.

Detailed Description Of The Invention

[0015] A dishwasher is generally designated by the reference numeral 10in the drawings. The dishwasher 10 has a washing chamber 12 in which ismounted a lower rack 14, a middle rack 16 and an upper rack 18. Thelower, middle and upper racks, 14, 16, and 18 are adapted to movebetween an extended position located substantially outside the washchamber 12 for loading objects to be washed, and a retracted positionwithin the chamber 12 for washing the objects.

[0016] More particularly, the lower rack 14 includes rollers 20 adaptedto roll upon a lip or ledge formed in the sidewalls of the wash chamber12 and upon the door 22 of the dishwasher 10 when the door is in thehorizontal open position. The middle rack 16 includes rollers 24 adaptedto roll along rails 26 mounted to the side walls of the chamber 12. Theupper rack includes rollers 28 adapted to roll along rails 30 mounted inthe opposite sides of the chamber 12. The rails 26 and 30 may betelescoping so that the middle rack 16 and upper rack 18 can be pulledfurther out of the wash chamber 12 for loading and unloading.

[0017] A water manifold 32 is operatively connected to the water pump ofthe dishwasher 10 and extends along the bottom and rear wall of the washchamber 12, as best seen in Figures 5 and 6. A lower spray arm 34, amiddle spray arm 36 and an upper spray arm 38 are fluidly connected tothe water manifold 32 and are associated with the lower rack 14, middlerack 16, and upper rack 18, respectively. The lower, middle, and upperspray arms 34, 36, 38 are located beneath each rack 14, 16, 18 and arespaced in close proximity to the bottoms of the racks. A fourth sprayarm 40 may also be provided above the upper rack 18. The lower spray arm34 and the fourth spray arm 40 are fixed with respect to the watermanifold 32. The middle spray arm 36 and upper spray arm 38 are fluidlyconnected to the water manifold 32 by wash tubes 42, 44, respectively.The wash tubes 42, 44 are connected to the middle and upper racks 16,18, respectively, by a clip 46 (Figure 2), and have an inner end adaptedto be releasably docked within middle and upper docking ports 48 and 50on the fluid manifold 32.

[0018] Preferably, the lower rack 14 is a flat, low profile rack withouttines. Thus, the lower rack 14 is adapted to hold flat or shallowobjects, such as cookie sheets, cake pans, and frying pans.

[0019] As best shown in Figures 1 and 4, the middle rack 16 has a slopedor stepped bottom portion 52 that provides a tall space on the rightside of wash chamber 12 between the lower rack 14 and middle rack 16.This right side tall space allows washing of taller objects on the rightside of lower rack 14. Similarly, the upper rack 18 has a sloped orstepped bottom portion 54 that provides a tall space on the left side ofthe wash chamber 12 between the middle rack 16 and upper rack 18. Thebottoms 52, 54 of the middle and upper racks 16, 18 slope in oppositedirections so that each rack can hold large objects, such as dinnerplates. As seen in Figure 4, the middle spray arm 36 and upper spray arm38 are angled or sloped so as to correspond with the slopes of themiddle and upper racks 16, 18, so that the water is sprayed in closeproximity to the bottom of the racks.

[0020] The middle rack 16 and upper rack 18 may be independentlyvertically adjusted, using conventional rack adjustment structure 58.For example, the adjustment mechanism 58 on each side of the middle andupper racks 16, 18 is shown in the drawings to include a block 60 with abar 62 extending through the block 58 for upward and downward movementin the block 58. Buttons 64 are depressed to allow the bars 62, and thusthe racks 16, 18 to be raised or lowered, as desired. Accordingly, themiddle docking port 48 and the upper docking port 50 each include upperand lower female ports 48A, 48B, 50A, 50B, as best seen in Figure 4.

[0021] Thus, the three rack dishwasher of the present invention havingseparate spray arms for each rack provides an efficient and effectivecleaning of objects held in each rack.

[0022] Whereas the invention has been shown and described in connectionwith the preferred embodiment thereof, it will be understood that anymodifications, substitutions, and additions may be made which are withinthe intended broad scope of the following claims. From the foregoing, itcan be seen that the present invention accomplishes at least all of thestated objectives.

What is Claimed is:
 1. A dishwasher comprising: a lower rack; a middlerack; an upper rack; a rotatable lower spray arm associated with thelower rack; a rotatable middle spray arm associated with the middlerack; and a rotatable upper spray arm associated with the upper rack. 2.The dishwasher of claim 1 wherein the spray arms are located beneath therespective racks and are spaced in close proximity to the respectiveracks.
 3. The dishwasher of claim 2 further comprising a fourth sprayarm located above the upper rack.
 4. The dishwasher of claim 1 whereinthe lower rack is without tines.
 5. The dishwasher of claim 1 whereinthe middle and upper racks each have a sloped bottom portion.
 6. Thedishwasher of claim 5 wherein the sloped bottom portions include aplurality of steps.
 7. The dishwasher of claim 5 wherein the bottomportions of the middle and upper racks are sloped in oppositedirections.
 8. The dishwasher of claim 5 wherein the middle and upperspray arms are sloped substantially similarly to the slope of the bottomportions of the middle and upper racks, respectively.
 9. The dishwasherof claim 1 wherein each of the middle and upper racks are verticallyadjustable, independent of one another.
 10. A dishwasher comprising: alower rack; a middle rack; an upper rack; the middle and upper rackseach having a sloped bottom portion, with the slope of each bottomportion extending in opposite directions.
 11. The dishwasher of claim 10further comprising lower, middle and upper spray arms associated withthe lower, middle and upper racks, respectively.
 12. The dishwasher ofclaim 11 wherein the spray arms are located beneath the respective racksand are spaced in close proximity to the respective racks.
 13. Thedishwasher of claim 11 further comprising a fourth spray arm locatedabove the upper rack.
 14. The dishwasher of claim 10 wherein the lowerrack is without tines.
 15. The dishwasher of claim 10 wherein each ofthe middle and upper racks are vertically adjustable, independent of oneanother.
 16. The dishwasher of claim 10 wherein the middle and upperspray arms are sloped substantially similarly to the slope of the bottomportions of the middle and upper racks, respectively.
 17. A dishwashercomprising: a flat lower rack without tines; a sloped middle rack; and asloped upper rack.
 18. A dishwasher of claim 17 further comprising alower spray arm, a middle spray arm, an upper spray arm, the lower,middle and upper spray arms being associated with the lower, middle andupper racks, respectively.
 19. The dishwasher of claim 18 wherein thespray arms are located beneath the respective racks and are spaced inclose proximity to the respective racks.
 20. The dishwasher of claim 19wherein the middle and upper racks slope in opposite directions.
 21. Thedishwasher of claim 20 wherein the middle and upper spray arms aresloped substantially similarly to the slope of the bottom portions ofthe middle and upper racks, respectively.
 22. The dishwasher of claim 19further comprising a fourth spray arm located above the upper rack. 23.The dishwasher of claim 17 wherein each of the middle and upper racksare vertically adjustable, independent of one another.
 24. Thedishwasher of claim 17 wherein the sloped portions of the middle andupper racks are stepped.
 25. A dishwasher comprising: a pair of rackseach having a sloped bottom portion; the bottom portions being sloped inopposite directions.
 26. The dishwasher of claim 25 further comprisingspray arms located beneath each of the racks, and each spray arm beingsloped to match the slope of the adjacent rack bottom portion.
 27. Thedishwasher of claim 25 further comprising a third rack beneath the pairof racks.
 28. The dishwasher of claim 25 wherein each bottom portion hasa plurality of steps.
 29. A dishwasher comprising: a pair of racks; eachrack being vertically adjustable.
 30. The dishwasher of claim 29 whereinthe adjustment of each rack is independent of one another.
 31. Thedishwasher of claim 29 further comprising a third rack beneath the pairof racks.
 32. The dishwasher of claim 29 further comprising a spray armassociated with each rack and being adjustable with each rack.